[PATCH RESEND v3] clk: return probe defer when DT clock not yet ready

Jean-Francois Moine
2014-02-08T13:25:07Z

At probe time, a clock device may not be ready when some other device
wants to use it.

This patch lets the functions clk_get/devm_clk_get return a probe defer
when the clock is defined in the DT but not yet available.

Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
---
resend v3:
- base kernel 3.14.0-rc1
- __clk_get() failure is fixed
resend v2: remove ASoc from subject (thank you, Mark)
resend: - patch subject change from
[PATCH v3 1/2] ASoC: kirkwood: clk: probe defer when clock not yet ready
- base kernel 3.13.0-rc1
v2: fix __clk_get() failure (from Russell King)
---
drivers/clk/clk.c | 2 +-
drivers/clk/clkdev.c | 2 ++
2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 5517944..32d84e9 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -2472,7 +2472,7 @@ EXPORT_SYMBOL_GPL(of_clk_del_provider);
struct clk *__of_clk_get_from_provider(struct of_phandle_args *clkspec)
{
struct of_clk_provider *provider;
- struct clk *clk = ERR_PTR(-ENOENT);
+ struct clk *clk = ERR_PTR(-EPROBE_DEFER);

/* Check if we have such a provider in our array */
list_for_each_entry(provider, &of_clk_providers, link) {
diff --git a/drivers/clk/clkdev.c b/drivers/clk/clkdev.c
index 48f6721..a360b2e 100644
--- a/drivers/clk/clkdev.c
+++ b/drivers/clk/clkdev.c
@@ -167,6 +167,8 @@ struct clk *clk_get(struct device *dev, const char *con_id)
clk = of_clk_get_by_name(dev->of_node, con_id);
if (!IS_ERR(clk))
return clk;
+ if (PTR_ERR(clk) == -EPROBE_DEFER)
+ return clk;
}

return clk_get_sys(dev_id, con_id);
--
1.9.0.rc3